The invention relates to a mechanism for filling and discharging a water tank of a toilet for flushing its toilet bowl.
The present invention provides improvements in a known toilet tank described in U.S. Pat. No. 4,791,689. The known mechanism and its general operation are described as follows.
A light manual pressure on a command handle on the outside of a toilet tank tilts a connected command lever in the toilet tank. The command lever is connected to a drainage buoy in a buoy base by a pulling chain to pull the drainage buoy from the buoy base when the command lever is tilted, whereupon the drainage buoy floats until the buoy base releases all the water from the tank by discharge into the toilet bowl. The same tilting action of the command lever also tilts an axle engaged by the command lever, which opens a valve on one end of the axle to allow new water to flow into the toilet tank. The discharge of water from the toilet tank is completed when there is insufficient water to float the drainage buoy and it settles down, by gravity, back into the buoy base, to close it again and stop the discharge of water, thereby allowing the toilet tank to refill with the new water from the valve on the axle. The pressure of the incoming water on the drainage buoy prevents its floating off the buoy base, thereby maintaining the base closed until the buoy is pulled therefrom by the command lever. The filling continues until the rise of the water level floats an axle floater on the opposite end of the axle from the valve sufficiently to put the axle in a vertical position and pull it vertically upwards. This closes the valve, and the tank is then full for another discharge operation. A pressure reducer at the valve can reduce the pressure of the water let into the tank if the water flows in at too high a pressure.